Roger Federer welcomed the return of Rafael Nadal, but will not spend much time worrying about his rival's progress as he concentrates on his own game with a late Wednesday start at the Rotterdam World Tennis.
The Swiss top seed, who is defending his trophy at the Ahoy stadium, put in a full day of public relations and photo op work before getting down to another serious training session on Monday.
The world No.2 said he has arrived relaxed and eager as he plays for the first time since losing a tight Australian Open semi-final to Andy Murray, then taking time off with his family in his homes in Dubai and Switzerland.
"I saw a few pictures of Rafa, last week," said Federer, who joked: "I see he's still a left-hander - and his shirts looked good."
But beyond the obvious natural curiosity, the 31-year-old with 17 Grand Slam titles has plenty on his own plate as he begins a run of events this week to be followed by the Dubai Open and the Indian Wells Masters next month in California.
"I'm happy to see him back and playing on the Tour," said the two-time Rotterdam champion, "That's a good thing.
"He seems to have good energy. I was surprised he lost a final against a player ranked outside the top 50. It's nice to see him playing well again.
"I'm sure he got a lot of information about his game last week (in Chile). He knows now how much strain he is putting on his body and how he is dealing with it."
While Nadal plays on clay in Sao Paulo, Federer will be bidding to make it a trophy hat-trick in Rotterdam, when he begins in the first round against Slovenia Grega Zemlja,
On court on opening day, French fifth seed Gilles Simon earned a 7-6 (7/3), 6-4 spot in the second round over German qualifier Daniel Brands, while compatriot Paul-Henri Mathieu fell to Slovak Martin Klizan 6-4, 3-6, 7-5
Romanian Victor Hanescu accounted for the week's first seed with his defeat of number seven Jerzy Janowicz 7-6 (7/4), 6-3. The Pole had made a breakthrough last autumn at Paris Bercy by reaching the final from a qualifying start.
Federer takes the top seeding ahead of Argentine Juan Martin del Potro, whom he beat for the title a year ago. France's Jo-Wilfried Tsonga is seeded third,
Federer took the opportunity to rebut criticism that he has abandoned Switzerland to its Davis Cup fate by opting out of the tie which his nation lost to the champion Czech Republic a week ago.
"Davis Cup is always difficult and I don't take that decision easily, I don't feel good when I see the doubles team play (a record) seven hours and then lose. That was one of the worst things for me.
"But I can't have it all or win it all. I have to take the decisions that are right for my career. I try to communicate with the team but that always boomerangs back at you.
"I hope I can play more in the future, but it's been tough the last few years. I also have a family and you have to understand that as well."